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<head>
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    <title>Document</title>
    <style>
        .box{
        	/* display:flex;表示使用的是弹性盒子 */
            display:flex;
            width: 500px;
        }
        .box div{
            height: 100px;
            border:1px #00a6f1 solid;
            /* 让所有弹性盒模型对象的子元素都有相同的长度，忽略它们内部的内容： */
            flex:1;
            -webkit-transition: all .3s;
            -moz-transition: all .3s;
            transition: all .3s;
        }
        .box div:hover{
        	/* 推开6个长度 */
            flex:6;
        }
    </style>
</head>
<body>
    <div class="box">
        <div></div>
        <div></div>
        <div></div>
        <div></div>
    </div>
</body>
</html>